1. Field of the Invention
The present invention relates to an image display control apparatus capable of controlling an image to be displayed on a display device arranged in a vehicle, enabling a driver and/or a passenger to watch the display device, by selecting the image from a plurality of images requested to be displayed by signals input from a plurality of in-vehicle units mounted on the vehicle via an input unit based on display priorities assigned to the images.
2. Description of the Related Art
Recently, a vehicle is commonly equipped with an image display device. Various in-vehicle units, for example, a navigation system, an audio system, and a sensor for checking a state or condition of the vehicle are connected to the image display device. Based on an input signal from any of the in-vehicle units, an operational status, a state or condition of the vehicle, or the like is displayed on a display screen of the image display device.
However, when a plurality of input signals from the in-vehicle units are input to the image display device at the same time, it is hard to display all images for the input signals on the display screen all together because a display area of the display screen has a limit. According to conventional technologies, when an image display device displays a first image thereon, if a request to display a second image is input to the image display device, the image display device eliminates the first image to display the second image, in most cases.
In this case, a display image is determined according to the latest display request. Therefore, the image display device displays the second image by switching from the first image even if the first image includes important information. In other words, even if the first image includes important information, and the second image includes less important information, the image display device displays the second image. Therefore, the important information may not get through to a driver and/or a passenger properly.
To solve the problems, for example, according to technologies disclosed in Japanese Patent Application Laid-open No. 2000-357300 and Japanese Patent Application Laid-open No. 2000-168474, images to be displayed on an image display device are ranked by a level of importance of information included in each of the images, and the image including information with a high level of importance is preferentially displayed on the image display device. Therefore, important information can get through to a driver and/or a passenger reliably.
Moreover, according to a technology disclosed in Japanese Patent Application Laid-open No. 2002-225592, when a vehicle is equipped with a plurality of image display devices, and a plurality of input signals from in-vehicle units are input at the same time, each of images for the input signals is controlled to be displayed on which of the image display devices depending on a level of importance of information included in each of the images. Therefore, the image including information with a high level of importance is preferentially displayed on the most appropriate image display device, so that the important information can get through to a driver and/or a passenger efficiently and effectively.
However, in such conventional technologies as disclosed in Japanese Patent Application Laid-open No. 2000-357300, Japanese Patent Application Laid-open No. 2000-168474, and Japanese Patent Application Laid-open No. 2002-225592, a display speed is constant because the same display process is always performed regardless of a level of importance of information included in an image. Therefore, when an image including information with urgency needs to be displayed, it takes a considerable time to display the image. As a result, the information with urgency cannot get through to the driver and/or the passenger immediately. In addition, even when an image withheld to be displayed due to its low level of importance is switched to be displayed, it takes a considerable time to display the image, so that a display timing of the image may be lost again.